Zones of plant hardinesstell us in which area a given plant can be grown. The frost resistance zone determines what is the average minimum temperature occurring in a given area. This allows you to select plants that can overwinter at such temperatures for the cultivation. See more preciselywhat are the plant hardiness zones , how to interpret them and what frost hardiness zones are in force in Poland. Article updated in 2019!
Zones of frost resistance of plants in Poland
Based on the study by W. Heinze and D. Schreiber from 1984
What are hardiness zones?
The first hardiness zones(also referred to as USDA climate zones) were designated in 1960 in the USA by the United States Department of Agriculture (USDA). The zones were designated on the basis of the average minimum temperature occurring in a given area. The designation of USDA climatic zones was to help in the correct selection of plants for planting andavoiding losses resulting from plant freezing
In 1984 W. Heinze and D. Schreiber, members of the German Dendrological Society, definedfrost resistance zones for Europe, including PolandThe division of zones developed at that time is still used today (header map, above). An identical map with the frost resistance zones can be found, among others in the Catalog of perennials recommended by the Polish Nurserymen Association published in 2018.
Note!It is worth emphasizing, however, that due to global warming, the above division into zones may no longer be valid.More information on this subject and newer frost resistance maps for Poland are presented later in the article. I encourage you to read the whole: -)
What frost resistance zones are there in Poland?
According to a study from 1984in Poland there are frost resistance zones 5B, 6A, 6B, 7A and 7BThe area covered by a given zone is shown on the map, while the range of minimum temperatures in a given zone is presented in table below. It is worth noting, however, that in the following years there were studies that indicate a shift in frost resistance zones due to global warming.According to the latest studies from 2016, there are zones 6B, 7A, 7B, 8A in Poland
How to interpret frost resistance zones?
As far as possible, in the descriptions of perennial plants (trees, shrubs and perennials) in our encyclopedia of plants we have included the number of the hardiness zone. A plant marked with a given zone can be grown in the indicated zone and warmer zonesIn colder zones (with a lower number) such a plant may freeze, depending on the weather pattern in the winter of a given year.
Example:a plant marked with zone 7A can be grown in zone 7A and zone 7B (warmer). In colder zones, i.e. 6B, 6A, 5B, such a plant may freeze. If you decide to grow the selected plant in a cooler zone than indicated, be sure to use frost and wind protection for the winter period.
Are the hardiness zones still valid?
The currently used hardiness zones were designated in 1984 , so quite a long time ago. In the face of more and more frequent and scientifically confirmed reports of climate warming, it is likely that the division into frost hardiness zones may no longer be valid.
Looking at the distribution of hardiness zones in Poland, it seems thatas the climate warms up, the boundaries of the zones may shift towards the south-east . Probably the coldest zone 5B has already disappeared, while the warmest zone 7B is increasing its area.
This theory was confirmed in 2012 by Marek Snowarski, and he described the results of his research on the website atlas-roslin.pl
Belowmap of frost resistance zones from 2012 according to the study by Mr. Marek Snowarski . As you can see, the coldest zone 5B has disappeared from the territory of Poland, and the boundaries of the other zones have shifted.
Frost resistance zones of plants in Poland 2012
Prepared by: Marek Snowarski, atlas-roslin.pl
As it turns out,even more recent study of USDA frost resistance zones from 2016, indicates further shifting of frost resistance zones . This information is published by Mr. Robert Sadowski on his blog in the article The change of frost resistance zones in Poland.
According to this study,in Poland there is no 6A zone anymore, and the coldest zone is 6B . There is also a new warm zone 8A from the north-west. Details are shown on the map below.
Frost resistance zones of plants in Poland 2016
Prepared by: Robert Sadowski, Drzewapolski.pl
It is worth getting acquainted withthe current map of frost resistance zones in Poland from 2016 , because it shows that we can now cultivate many new species and interesting varieties of plants, which a dozen or so years ago it wasn't worth planting. On the other hand, however, it is worth being cautious, as it is not certain what the direction of climate change will be in the future. However, further warming of the climate is most likely. So we are waiting for an even newer and more up-to-date map of frost resistance zones: -)
